U.S. Pat. No. 5,203,698 discloses a wet foam sandblaster used for oral care. A bubble foam laden with abrasive particles is propelled through a small nozzle by gas pressure. The system has very specific applications in the dental industry for 1) general cleaning of teeth such as removal of tobacco, tea and other stains; 2) for selectively abrading away carious enamel, 3) cleaning prosthodontic restorations, 4) abrading various tooth and restorative materials in preparation for bonding, and 5) periodontal pocket cleaning with osteophylic abrasives; and 6) cleaning of occlusal pits and fissures for sealing. In addition, the system has numerous applications in cleaning and etching materials in the jewelry, semi-conductor, automotive and other industries.
The apparatus for cleaning teeth and other surfaces comprises a canister capable of being sealed and pressurized, and receiving a mixture of liquid, abrasive particles and wetting agent. The canister also has a means to receive a stream of pressurized gas, a means to disperse pressurized gas into the mixture of liquid, abrasive particles and wetting agent thereby causing a formation of foam and urging the abrasive particles to become entrained into the foam. Also provided are a means to direct the abrasive laden foam to the surface to be cleaned, and a means to control the flow of the abrasive laden foam.
The product shown in the '698 patent is sold by Danville Engineering of San Ramon, Calif. This product is designed for use by a dental professional in a dentist office and not for home use by individual consumers. As such, some of the features of the product make it not suitable for home use. For example, the Danville product does not include an integral air compressor and electric motor to run the compressor. Accordingly, a consumer would have to buy a separate air compressor and place it in their bathroom along with the Danville product in order to use the system. Such an arrangement is inconvenient and would clutter up the bathroom counter.
Additionally, the Danville product is operated at an air pressure of 40-60 psi for light cleaning. However, when the extended handpiece is used on the product, the air pressure needed is at the upper end of the 40-60 psi range (assumed to be about 55-60 psi). While this pressure range (55-60) is safe when the product is being used by a dental professional on a patients teeth, it could be too high to be safely used by an individual in their home.
In order for the Danville product to accomplish certain functions, it is designed to be operated with a slurry having a volumetric ratio of 2 parts water to one part powder. Such a slurry represents an aggressive concentration that should preferably be administered by a dental professional and not a consumer during home use.
Air Force Inc. of Holland, Mich. sells a product called the Dental Air Force. This system uses air mixed with water and dental cleaner (sodium bicarbonate) to remove food and plaque off the teeth. Air delivers cleaner into tiny spaces between teeth and along the gums. Air and cleaner are sprayed from the end of a slim tip to remove plaque from the oral cavity.
A drawback to this system is that every time it is used, a portion of the hand-piece must be opened up, a new cup of dental cleaner must be inserted into the hand-piece, and then the portion of the hand-piece is reattached. This operation is inconvenient. Further, the operator must wait 20-30 seconds for the cup to fill with water before the unit can be used to clean the teeth. This is yet another inconvenience. Further, because the powder is placed in the hand-piece, the hand-piece is relatively large, thus making it awkward to use.
Deldent Ltd discloses a series of dental products which appear to be for use by dental professionals and not by people in their homes. This company sells several air polishing units which the company claims operates at 35 psi.